Apparatus for breaking up lumpy material

ABSTRACT

Pulverizing equipment including a disc rotating on a vertical axis and having an inner row of impact elements thereon, which first engage the material and break it up and accelerate it radially outwardly toward an outer row of impact elements on the disc which cooperate with a surrounding stationary row of impact elements to complete the breaking up of the material. A housing surrounds the disc and has outlet means at the periphery of the disc for the withdrawal of pulverized material. A blower beneath the disc may supply air to the region of the periphery of the disc to assist in the withdrawal of the pulverized material from the housing.

. Waited tates Patent Jung et a1.

[is] 3,6@,4l75

[ 1 Feb. 8, 1972 [54] APPARATUS FOR BREAKIING UP LIUMFY MATERIAL [73] Assignee: L 8: C Steinmuller Gmbil, Gumrnersbach,

Rhineland, Germany 22 Filed: Apr. 1, 1969 21 Appl.No.: 812,207

[58] Field of Search ..241/188 A, 188,55, 56, 47, 241/191, 192, 275

[56] References Cited UNITED STATES PATENTS Riley ..241/188 A X Prouty ..241/188 A X Teale ..241/l88 X Primary Examiner-Donald G. Kelly Att0rneyWalter Becker [57] ABSTRACT Pulverizing equipment including a disc rotating on a verticai axis and having an inner row of impact elements thereon, which first engage the material and break it up and accelerate it radially outwardly toward an outer row of impact elements on the disc which cooperate with a surrounding stationary row of impact elements to complete the breaking up of the material. A housing surrounds the disc and has outlet means at the periphery of the disc for the withdrawal of pulverized material. A blower beneath the disc may supply air to the region of the periphery of the disc to assist in the withdrawal of the pulverized material from the housing.

14 Claims, 6 Drawing Figures PATENIEDFEB 81912 v 3 640 475 sums-or 4 lil //v VE/V r09 9 APPARATUS FOR BREAKING UP LUMPY MATERIAL The present invention relates to a device for breaking up lumpy material according to which the material to be broken up drops in a free fall axially into a breaking up device.

When breaking up material, it is known to introduce the same centrally into a grinding chamber and through a rotating dispersing body to distribute the material uniformly outwardly to an oppositely rotating plate grate where the breaking up operation is effected.

The decisive drawback inherent thereto consists in that an insufficient grinding will be obtained when the relative speed between material to be ground and the breaking up element is too low, as a result of which a sifting of the ground material becomes necessary. The sifting operation in its turn represents an additional working step and affects the breaking up device because with the so-called grit, also a considerable portion of the material of sufficient fineness will flow back into the breaking up system. Furthermore, the sifter represents an additional element subjected to wear so that additional costs are encountered with regard to both devices, the breaking up device as well as the sifter. If the circumferential speed of the breaking up elements is high, considerable ventilation losses are encountered.

It is, therefore, an object of the present invention to provide apparatus for breaking up lumpy material, especially an impact crusher, which will realize a fine grinding of the material while the latter passes through the breaking up device only once.

It is another object of this invention to provide a device as set forth in the preceding paragraph, which will keep ventilation losses at a minimum.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 diagrammatically illustrates a vertical section through an impact pulverizer according to the present invention.

FIG. 2 represents a section taken along the line 11-11 of FIG. I.

FIG. 3 represents a vertical section through a modified impact pulverizer according t'o the invention.

FIG. 4 represents a section taken along the line IV-IV of FIG. 3.

FIG. 5 illustrates still another embodiment of the invention according to which the entire accelerating system, breaking up system and blower system are arranged on a common motor shaft.

FIG. 6 shows still another embodiment of the invention partly in section, according to which the accelerating system, the breaking up system and the blower system are arranged on a shaft of their own which is connected to the motor shaft by means ofa coupling or clutch. v

The above and other objects have been realized according to the present invention which is characterized primarily in that the material is conveyed to a rotating plate grate where while being subjected to a prebreaking-up operation, the material is accelerated outwardly and is conveyed into at least a further rotating plate grate where in cooperation with the latter and a selectively arranged rigid grate the material is broken up to the final granular size.

According to a further development of the present invention, the rotating plate grates associated with each other may rotate in the same or opposite direction and at the same or different angular velocities. The extent to which the individual rotating systems are employed for the grinding operation depends primarily on the character of the material to be broken up and also on the desired degree of grinding.

Experience has shown that the breaking up elements should rotate within a velocity range of from 80 to 250 meters per second in order to obtain the best results in connection with the present invention.

A preferred device according to the present invention in the form of an impact pulverizer with breaking up elements rotatable about a vertical axis and with stationary breaking up elements and a central supply for the material to be broken up is characterized primarily in that below the feeding means, preferably designed as an annular passage, there is in a closed breaking up chamber provided a rotating accelerating grate with a precrushing effect the individual elements of which are connected to a plane disc-shaped supporting member which latter is fixedly connected to another supporting element arranged on a common drive shaft. The outer marginal area of said last mentioned supporting element is provided with additional breaking up elements which cooperate with stationary elements arranged rotation-symmetrically with regard to the rotating breaking up elements.

In order to be able to withdraw the broken up material from the region of the breaking up chamber, the latter is, in conformity with the present invention, surrounded by a spirally shaped housing with at least one outlet. The spiral design of the housing will, when providing a plurality of discharge openings yield the advantage that the total flow of the material is substantially uniformly divided into partial flows. The same effect may also be realized in conformity with the present invention if the outer area of the breaking up or crushing chamber is surrounded by a cylindrical housing which is likewise equipped with outlets for the material being crushed. When employing a cylindrical housing, the said outlets may be arranged at the top or bottom or on the sides. The connection of the accelerating and crushing elements is likewise of importance for the efficiency of the device according to the invention.

Therefore, according to a further development of the invention, it is suggested that the individual elements of the accelerating grate are guided in dovetailed recesses of a supporting element and are held from the top by means of a disc, whereas the crushing elements equipped with a foot are located in correspondingly designed recesses of a further discshape; supporting element and during a standstill are prevented from dropping out by centrally located holding means while during operation they are held by frictional engagement between the supporting and crushing elements. The holding means intended for the elements of the crushing grate may be in the form of a dish spring or of a disc body. Naturally, also other heretofore known machine elements may be employed for this purpose.

In order to be able to feed the material which leaves the accelerating grate in a desired manner to the crushing grate, it is suggested in conformity with the present invention to provide a filling body in the free space between the elements of the accelerating grate and the elements of the crushing grate. This filling body forms a unit with the upper housing closure means or is preferably connected thereto by welding, by screws, by cementing, or the like. The filling body is preventing the crushed material from moving outwardly through the gap formed by the rotating crushing elements and the upper housing closure means without being hit by the crushing elements.

In order, following the crushing operation, to withdraw the crushed material from the crushing chamber, it is suggested according to the invention, to provide a blower wheel below the disc-shaped supporting element and on a common motor shaft. However, if desired, the blower may be arranged separately from the crushing system proper.

The degree of crushing may be controlled by varying the circumferential speed of the crushing elements and also by varying the pitch angle of the crushing elements. If desired, the individual elements of the accelerating grate, of the rotating grate, and of the stationary crushing grate may be pitched radially or relative to the radial direction at an angle.

Referring now to the drawings in detail, it will be noted that the material to be crushed drops in a free fall through an annular passage 1 into a centrally located accelerating grate 2 by means of which the material to be crushed is accelerated to the necessary radial velocity which will enable the material to enter the outer crushing grate 3 which rotates at higher speed. During its flight between the accelerating grate 2 and the crushing grate 3, the material moves through a gap 7 formed by the rotating disc-shaped supporting element 4 and the stationary filling body 6 connected to the housing cover 5. The crushed material leaves the crushing grate 3 substantially tangentially and impacts vertically upon the crushing elements of the stationary crushing grate 8 where a post-crushing or pulverization occurs. The thus crushed material passes to the outer range 9 of the crushing chamber which crushing chamber, in conformity with FIG. 2, is surrounded by a spirally shaped housing 10. According to the embodiment of FIG. 2, two outer ranges 9 of the grinding chamber are each provided with a withdrawing opening or outlet ll, 12. In view of the simultaneous stresses exerted upon the entire crushing grate 3, the material leaves the system in the form of a uniform flow. The arrangement of the outlets 11 and 12 at a corresponding angular position permits a dividing up of the total flow in conformity with agiven branching requirement.

As will be seen from FIGS. 3 and 4, the arrangement of the withdrawal connections I3 in the crushing chamber 9 between the housing mantle'l0 and the stationary crushing grate 8 will at a corresponding angular pitch make possible a dividing up of the material to be crushed in conformity with the requirements.

To permit an easy exchange of the accelerating elements 2, these elements are inserted in dove-tailed recesses 14 and by means of a cover disc 15 are prevented from accidentally dropping out.

The crushing elements 3 of the rotating grate are inserted from below into corresponding recesses of the dise-shaped supporting element 4. The individual elements 3 are provided with a foot 16 which engages a correspondingly shaped recess 17 of the supporting element 4. During a standstill of the device, the individual crushing elements are prevented by holding means 18 from accidentally dropping out. The holding means 18 may be designed in the manner of a dish spring or, if preferred, as disc bodyfThe crushing element itself is so designed that its center of gravity is located above the discshaped supporting element d, and the attacking centrifugal force will tend to pull the crushing element out in the upward direction. This is prevented by the positive engagement between the foot 16 and the recess 17.

The crushed material is, in conformity with the invention, withdrawn pneumatically from the crushing chamber. To this end, there is'provided a blower wheel 19 which together with the accelerating and crushing system is arranged on the common motor drive shaft 20 (FIG. 5). The blower wheel 19 may, however, also be arranged together with the accelerating system and the crushing system on a shaft 21 of its own (FIG. 6), said shaft 21 being connected by a clutch 22 to the motor drive shaft 20.

The advantages realized by the present impact crusher are seen in particular in the fact that the material to be ground can be broken up and crushed while passing through the device only once. The granular size to which the material is to be crushed may, of course, be varied. In this connection it is possible to adapt the crusher to the respective properties of the material to be crushed". This can be realized on one hand by selecting a circumferential speed which is in conformity with the properties of the material to be crushed and on the other hand by pitching the crushing elements in the stationary and rotating grate with regard to the radial direction. At highcircumferential speeds, it is possible with a very small volume of the crusher to obtain a considerable output.

In view of the disc-shaped supporting elements being provided with smooth surfaces on the top side of which at the outer marginal area there are located the crushing elements proper, the height of which equals a few diameters of the grain of the material to be processed, the ventilation losses of the otherwise smooth supporting elements will also at highcircumferential speeds remain relatively low. The impact angle of the material to be crushed upon the crusher elements of the stationary and resting grate are within approximately 90 within the range which is most favorable with regard to wear and the crushing operation.

As will be seen from the above, in view of the high relative velocity between the breaking up elements and the material to be broken up, the desired granular size can be realized while the material passes only once through the breaking up device so that a sifting operation will be saved. On the other hand, the high circumferential speed makes it possible to keep the height of the plate grate low whereby the ventilation losses can, in spite of the high speed, be kept at a minimum.

It is, of course, to be understood that the present invention is, by no means, limited to the particular method and apparatus referred to above, but also comprises any modifications within the scope of the appended claims.

We claim:

I. In an impact pulverizer: a housing defining a closed chamber, disc means rotatable on a vertical axis in said chamber, a radially inner and a radially outer circumferential row of spaced apart impact elements on said disc means and upstanding therefrom, feeding means for feeding material to be pulverized vertically downwardly into said chamber to said radially inner row of impact elements for preliminary crushing of said material thereby outwardly toward said radially outer row of impact elements, a further circumferential row of spaced apart impact elements concentric with and adjacent to said radially outer row of impact elements and carried by said housing, said further row of impact elements cooperating with said radially outer row of impact elements to perform the final pulverizing of said material in said pulverizer, said disc means comprising a smaller central disc having peripheral notches therein which widen out in the radially inward direction, said radially inner row of impact elements having foot portions thereon fitting said notches and being adapted for insertion into the notches in the axial direction, and a clamp disc overlying said notches and retainingsaid impact elements therein.

2. An impact pulverizer according to claim 1, in which said feeding means is an annular passage opening at its lower end directly over said radially inner row of impact elements.

3. An impact pulverizer according to claim 2, in which said housing is spiral shaped in the region thereof surrounding said disc means and includes at least one substantially tangential outlet for pulverized material.

4. An impact pulverizer according to claim 2, in which said housing is cylindrical in the region thereof surrounding said disc means and is provided with outlet means for the withdrawal of pulverized material from the pulverizer.

5. An impact pulverizer according to claim 1, in which said disc means includes a larger disc having axial apertures at the periphery, said outer row of impact elements being insertable axially into said apertures and having an enlarged portion at one end to abutone side of said larger disc, and a further clamp member engaging said enlarged ends of the impact elements of said outer row thereof to hold them in position in said apertures.

6. An impact pulverizer according to claim 5, in which the center of gravity of each impact element of said outer row thereof is located on the opposite side of said larger disc from the said enlarged end of the respective impact element.

7. An impact pulverizer according to claim 6, in which said inner and outer rows of impact elements extend vertically upwardly from said disc means and said housing includes an upper wall extending horizontally over said rows of impact elements on said disc means, and a filler member on the underside of said upper wall of the housing dependent therefrom in the radial region between said rows of impact elements on the disc means.

8. An impact pulverizer according to claim 7, which in cludes a drive shaft connected to said disc means in the center thereof and extending downwardly therefrom, and an air im peller in said housing on said shaft beneath the disc means and operable for impelling air radially outwardly in the housing beneath said disc means.

9. An impact pulverizer according to claim 8, which includesa drive motor having an output shaft coaxial with said drive shaft, and clutch means coupling said motor output shaft to said drive shaft.

l0. ln an impact crusher apparatus, a housing having a cover means, a disc body mounted in said housing for rotation about a vertical axis of rotation, an inner cascade of pulverizing elements mounted in said housing above the plane of said disc body for rotation about said axis, an outer cascade of pulverizing elements arranged in horizontal, coplanar relationship to said inner cascade and spaced radially outwardly from said inner cascade and mounted for rotation about said axis, an impact cascade of impact crusher elements fixed to said housing cover means in horizontal, coplanar relationship outwardly of said outer, rotatable cascade, and an axial supply for material to be pulverized comprising a ring-passage-forming means coaxial with said axis and opening into said housing with said pulverizing elements of said inner cascade directly below and in alignment with said ring-passage-forming means, said radially spaced pulverizing elements of said inner and outer cascades defining a ring-formed space means free of pulverizing elements in radial direction between the inner nd outer cascades,

11. An impact crusher apparatus according to claim 10, in which a bottom portion of said housing cover means lies-in an area between said pulverizing elements of rotating cascade means, and the upper edges of said pulverizing elements of said outer cascade lie in substantially the plane of said bottom portion of said housing cover means.

12. An impact crusher apparatus according to claim 11, in which swallow-tail-formed recess means are provided for guidance of pulverizing elements of the inner rotating cascade and maintained on top of one disc body, base portions of pulverizing elements of the outer rotating cascade being formed complementary to recesses in thelarger disc body, dish spring hol;ing means hindering drop out of said base portions during standstill, and that hold said base portions in complementary interfit with pulverizing elements during operation.

13. An impact crusher apparatus according to claim 12, in which a spiral-form-embodied housing having at least one exit encompasses outer range of pulverizing space.

14. An impact crusher apparatus according to claim 12, in which a cylindrical housing having withdrawal connections for pulverizing elements output is provided around outer range of the pulverizing space. 

1. In an impact pulverizer: a housing defining a closed chamber, disc means rotatable on a vertical axis in said chamber, a radially inner and a radially outer circumferential row of spaced apart impact elements on said disc means and upstanding therefrom, feeding means for feeding material to be pulverized vertically downwardly into said chamber to said radially inner row of impact elements for preliminary crushing of said material thereby outwardly toward said radially outer row of impact elements, a further circumferential row of spaced apart impact elements concentric with and adjacent to said radially outer row of impact elements and carried by said housing, said further row of impact elements cooperating with said radially outer row of impact elements to perform the final pulverizing of said material in said pulverizer, said disc means comprising a smaller central disc having peripheral notches therein which widen out in the radially inward direction, said radially inner row of impact elements having foot portions thereon fitting said notches and being adapted for insertion into the notches in the axial direction, and a clamp disc overlying said notches and retaining said impact elements therein.
 2. An impact pulverizer according to claim 1, in which said feeding means is an annular passage opening at its lower end directly over said radially inner row of impact elements.
 3. An impact pulverizer according to claim 2, in which said housing is spiral shaped in the region thereOf surrounding said disc means and includes at least one substantially tangential outlet for pulverized material.
 4. An impact pulverizer according to claim 2, in which said housing is cylindrical in the region thereof surrounding said disc means and is provided with outlet means for the withdrawal of pulverized material from the pulverizer.
 5. An impact pulverizer according to claim 1, in which said disc means includes a larger disc having axial apertures at the periphery, said outer row of impact elements being insertable axially into said apertures and having an enlarged portion at one end to abut one side of said larger disc, and a further clamp member engaging said enlarged ends of the impact elements of said outer row thereof to hold them in position in said apertures.
 6. An impact pulverizer according to claim 5, in which the center of gravity of each impact element of said outer row thereof is located on the opposite side of said larger disc from the said enlarged end of the respective impact element.
 7. An impact pulverizer according to claim 6, in which said inner and outer rows of impact elements extend vertically upwardly from said disc means and said housing includes an upper wall extending horizontally over said rows of impact elements on said disc means, and a filler member on the underside of said upper wall of the housing dependant therefrom in the radial region between said rows of impact elements on the disc means.
 8. An impact pulverizer according to claim 7, which includes a drive shaft connected to said disc means in the center thereof and extending downwardly therefrom, and an air impeller in said housing on said shaft beneath the disc means and operable for impelling air radially outwardly in the housing beneath said disc means.
 9. An impact pulverizer according to claim 8, which includes a drive motor having an output shaft coaxial with said drive shaft, and clutch means coupling said motor output shaft to said drive shaft.
 10. In an impact crusher apparatus, a housing having a cover means, a disc body mounted in said housing for rotation about a vertical axis of rotation, an inner cascade of pulverizing elements mounted in said housing above the plane of said disc body for rotation about said axis, an outer cascade of pulverizing elements arranged in horizontal, coplanar relationship to said inner cascade and spaced radially outwardly from said inner cascade and mounted for rotation about said axis, an impact cascade of impact crusher elements fixed to said housing cover means in horizontal, coplanar relationship outwardly of said outer, rotatable cascade, and an axial supply for material to be pulverized comprising a ring-passage-forming means coaxial with said axis and opening into said housing with said pulverizing elements of said inner cascade directly below and in alignment with said ring-passage-forming means, said radially spaced pulverizing elements of said inner and outer cascades defining a ring-formed space means free of pulverizing elements in radial direction between the inner and outer cascades.
 11. An impact crusher apparatus according to claim 10, in which a bottom portion of said housing cover means lies in an area between said pulverizing elements of rotating cascade means, and the upper edges of said pulverizing elements of said outer cascade lie in substantially the plane of said bottom portion of said housing cover means.
 12. An impact crusher apparatus according to claim 11, in which swallow-tail-formed recess means are provided for guidance of pulverizing elements of the inner rotating cascade and maintained on top by one disc body, base portions of pulverizing elements of the outer rotating cascade being formed complementary to recesses in the larger disc body, dish spring holding means hindering drop out of said base portions during standstill, and that hold said base portions in complementary interfit with pulverizing elements during operation.
 13. An impact crusher apparatus accOrding to claim 12, in which a spiral-form-embodied housing having at least one exit encompasses outer range of pulverizing space.
 14. An impact crusher apparatus according to claim 12, in which a cylindrical housing having withdrawal connections for pulverizing elements output is provided around outer range of the pulverizing space. 